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Many of us have had the fear of looking outside the window of an airplane and seeing the engine fail. But what would happen? Can a plane fly with one engine?
Most commercial airplanes have two engines, but they are designed to be able to fly almost exactly the same if one fails. So if an engine fails mid-flight, a pilot should have little to no problems getting the plane to land safely with only one engine.
We know that might sound a little crazy at first, but it’s true! Although it’s likely that you won’t ever have to experience this, if an engine does fail during a flight you’re on, don’t worry! The plane is designed to be able to fly for hours on only one engine. So the pilot shouldn’t have a problem finding a runway to make a safe landing. More often than not, you’ll even end up making it to your final destination as planned.
Just like all the other articles you’ll find on our site, everything you find below has been thoroughly vetted to ensure its accuracy. Not only is all the information researched and attained through other aviation experts and plane manufacturers themselves, we’ve combed through everything carefully to provide only the most accurate information we can for our readers.
Can A Plane Fly With Only One Engine Working?
Let’s preface this by saying that for the sake of this article, we are going to talk mostly about passenger jets (commercial airplanes) that have more than one engine. This is because if a single-engine plane has an engine failure, that of course means that all of its engines have failed, which is also addressed later on in this article as well! So let’s dive in.
Can a commercial passenger jet fly if one of its engines have failed?
The short answer is that yes, it can. A passenger jet with two or more engines can fly almost just as well with an engine failure as it can with all engines running as they should. The longer answer is of course still yes, but with a bit more nuance than that. So let’s take a much deeper look into what actually happens if a plane has an engine failure and how the plane is able to continue flying.
What Happens If An Engine Fails On A Plane?
Being a passenger on a plane when an engine goes out can certainly be a scary experience. But being the pilot on the same plane is undoubtedly much more stressful. But the good thing is that in either case, most planes can actually fly perfectly fine even if they’ve experienced an engine failure. This is because passenger jets typically have two (or more) engines and are capable of flying with just one. So a mid-flight engine failure is not the end of the world.
So if a passenger jet experiences engine failure during flight, more often than not the flight can continue on as planned. But if for one reason or another the crew has deemed it an emergency, they should have little to no problems reaching the next safe place to land and landing the plane as normal.
Take the Boeing 777, for example. This popular passenger jet has two engines to power the plane through the skies. If one of them were to fail mid-flight, the Boeing 777 is actually designed to be able to fly for 5.5 hours on just one engine. That’s long enough to complete just about any domestic flight in the United States, largely without issue.
The biggest problem a plane might face is a slight loss in power, which will result in losing a bit of maximum altitude. But it shouldn't be drastic enough to really start to cause any serious issues. The real problems start to pop up if all of the plane's engines fail.
Can A Plane Fly If All Of Its Engines Fail?
Now that you know that a plane can fly — largely perfectly fine — with only one engine, we know what you’re thinking next. Well, then what happens if all of a plane’s engines fail during a flight? That’s where it can start to get tricky, and it’s a situation that we hope you never find yourself in, as either a pilot or a passenger.
As you have probably surmised, if a plane loses power in all of its engines, it will no longer have any thrust and power of its own. If you’ve read our piece on how planes fly, you know that thrust and power are needed to push a plane forward through the air to overcome drag and stay airborne. So without power, the plane will start to drift downwards.
The good thing about planes is that they will not just suddenly crash if all the engines fail. Instead, an experienced pilot will be able to take the plane into a controlled glide — a powerless maneuver that lets the pilot control the plane as it slowly descends. While gliding, the pilot will radio Air Traffic Control and find the nearest runway or safe place to land and guide the plane towards it.
If the pilot can get the gliding plane to somewhere safe to safe, they can land almost as normal. If they cannot reach a runway, a pilot may have to take more drastic measures like landing in a wide open field or even on a big body of water. Either way, engine failure does not automatically mean the plane goes down. An experienced pilot will be able to make the most out of a bad situation and have an attempt at a safe landing.
How Many Engines Do Planes Have?
The number of engines on a plane depends on the type of plane and what it’s designed to do. But typically, the number of engines will be somewhere between one and four. When you’re talking potentially tens of thousands of pounds of thrust, the difference between one and four engines is massive. So what types of planes have different numbers of engines?
The simplest answer to this question begins with single-engine aircraft, such as smaller aircraft that you might learn to fly in or might even own yourself. As their class description alludes to, these smaller aircraft have just one engine. And it’s typically a propeller or piston engine, not the big jet engines that we’re talking about in this article.
The most common answer to how many engines a plane has is two. On nearly every model passenger jet out there, they come outfitted with two engines from the factory. Due to their size and design, a single engine is not really plausible. And more than two engines are typically not needed since these jet engines are capable of producing such extreme amounts of power and thrust.
There are, however, some passenger jets with four engines. These only include the Boeing 747, Airbus A340, and Airbus A380. These planes have more engines because of just how big they are and how many passengers they carry. These massive planes require more thrust to get them going than their smaller counterparts, so four jet engines are used.
In any case, the higher the number of engines, the less of a potential issue a single-engine failure will cause.
The Most Common Reasons That Plane Engines Fail
Now that you have an idea about the consequences of engine failure and if a plane can still fly or not, let’s take a quick look at some of the most common causes of plane engine failure. The following common reasons for known engine failure come directly from the National Transportation Safety Board (NTSB):
- Fuel issues including delivery, exhaustion, contamination, or mismanagement.
- An internal failure such as worn hoses and fittings or bad or broken parts that are not replaced.
- Induction icing caused by pilot error forgetting to use the proper heat generation during descent.
- Fuel starvation caused by pilot error in incorrectly accessing fuel tanks (or not accessing them at all when needed).